Modify commercial aircraft transponders so that when they are set to one of the recognized distress codes, they send a signal to the AirPhone satellite phone controllers on board. AirPhone would then enable all of the on-board telephones to place a 911 calls (without requiring a credit card to activate
the phones). Dialing 911 would connect callers to the closest FAA regional traffic control center, rather than the closest municipal 911 call center.

I don't know how many connections AirPhone supports from a single aircraft. I figure a few passengers would get through before the AirPhone system was saturated, and the FAA would have to decide which callers to keep on line, either by location in the aircraft or perhaps by apparent level of panic. The satellite phone system could also begin recording all calls made from that point forward, helping to provide a record of events in the cabin.

Might be an interesting discussion nonetheless, integrating the phone system to the rest of the plane communications in some fashion for a smarter system overall could be beneficial in trying to size up a situation.

Perhaps all phones could instantly go 'live' undetected at the push of a button, in order to listen in on the whole plane. Trade some bandwidth for compressed audio, and there you have it.

[DrCurry], I absolutely do not want to create more of those tragic calls from doomed passengers. That's why I'd enable the phones for just 911 calls to the FAA. As with black box recordings, transcripts of calls would be carefully controlled, rather than grabbed and replayed by the press.

[RF], situational awareness for the authorities is my intent. I like your suggestion that all phones go live, though I think the phones have to be removed from their cradles to keep from obstructing the microphones.

[UB], agreed, (almost) half-baked by [solomungus], and a good idea.

My original idea was a fixed cockpit and cabin surveillance system with cameras and microphones linked to the AirPhone system. My intent was to create a "black-box" record of events that wasn't stored on the airplane, making the record of events available almost instantly and not subject to destruction in the event of a catastrophe. I opted for this idea instead because I figured that the cameras and mikes might not be in the right locations for any given incident, and that passengers are probably good sources of information. The original idea may have been the better one.

I remember it took them years to accept GPS and then with some misgivings. They prefer tried and tested (and awful IMO) devices like radio beacons.

And these guys are almost 100% by the book. If you called them up from a cellphone or a satellite phone and gave your mayday call instead of ringing their bells on 121.5 in the normal way, you'd probably hit the ground before they were able to confirm it wasn't a hoax.

- Pilots enter one of their normal 4-digit transponder codes for aiplanes in distress, I'm well aware that 911 isn't one of them. For that matter, you can't dial a 9 into a transponder, the range of possible values is 0-7 in each position.

- Passengers dial 911 on the built-in AirPhones. I don't know what you'd normally get by dialing 911 on an AirPhone, I'm proposing that instead of a police department that can't help, you get the FAA who might be able to.

- Passengers don't make mayday calls per say, but might provide situaltional awareness for the FAA. The FAA knows the calls aren't hoaxes because the calls are routed by AirPhone - no distress code in the transponder, no inflight 911 from AirPhone.